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Germinomas are the most common type of germ cell tumor occurring commonly before the second decade of life. Because of the radiosensitivity of germinomas, traditional treatment following diagnosis has been conventional radiotherapy. The desire to defer radiotherapy to avoid the delayed neurocognitive effects has led researchers to investigate the use of up front chemotherapy. A major limitation in using chemotherapy for brain tumors has been the inability to deliver drugs across the blood brain barrier. The blood brain barrier consortium has developed chemotherapy protocols for patients with malignant brain tumors through the use of reversible osmotic opening of the blood brain barrier. While the patient is under general anesthesia, osmotic opening or disruption is achieved by a 30-second intracarotid infusion of mannitol. The mannitol infusion is followed by both intraarterial and intravenous chemotherapy. By administering chemotherapy in conjunction with blood brain barrier disruption, drug delivery to the tumor and the brain around tumor is increased.  相似文献   
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We present an adenoid cystic carcinoma of the base of tongue in a 48-year-old male with a restricted chromosomal alteration by cytogenetic and spectral karyotypic analysis (SKY). SKY and G-banding analyses identified the t(6;14)(q25;q13) as the sole structural aberration in all metaphases analyzed. This finding supports a critical role for this event in the development of this tumor. The implications of chromosome 6q translocation in this case and in previously reported adenoid cystic carcinomas are highlighted and discussed.  相似文献   
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Gangliosides were isolated from human cataractous nuclei by solvent extraction, dialysis, and thin-layer chromatography and compared to gangliosides present in human whole normal and cataractous lenses. Three predominant gangliosides were tentatively identified as GM1, GM3, and GD1a, and several other resorcinol-positive components were observed in each of the sets of lens tissue. Thin-layer chromatographic patterns were similar, although some minor and possibly significant differences in band intensities were observed when chromatograms of gangliosides from cataractous nuclei and cataractous whole lenses were visually compared with those of whole normal lenses. Total ganglioside extracts were methanolyzed and the fatty acid methyl esters extracted with hexane and resolved by gas chromatography. Nervonic acid (C-24:1) content was increased in cataractous nuclei as compared to normal and cataractous whole lenses.  相似文献   
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Human insulin-receptor gene   总被引:16,自引:0,他引:16  
S Seino  M Seino  G I Bell 《Diabetes》1990,39(2):129-133
The human insulin-receptor (hINSR) gene spans a region of greater than 120,000 base pairs (bp) on the short arm of chromosome 19. It is comprised of 22 exons or coding regions that vary in size from 36 to greater than 2500 bp. To a large degree, the introns appear to divide the hINSR gene into segments that encode structural and/or functional elements of the hINSR protein. The exon-intron organization of the hINSR gene provides a clue to the evolutionary history of this gene and suggests that it is a mosaic constructed from protein-coding regions recruited from other genes. Eight mutations in the hINSR gene that result in expression of structurally abnormal proteins have been described. These mutations are associated with insulin resistance and provide insight into the role of the hINSR gene in the development of diabetes mellitus.  相似文献   
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Elevated levels of serum cholesterol are a major risk factor for coronary artery disease, yet few studies have investigated the extent to which practicing physicians recognize and treat their patients with hyperlipidemia. A retrospective chart review was performed on 93 patients who had documented cholesterol levels greater than or equal to 6.20 mmol/L (240 mg/dL) in an outpatient setting to determine the degree of recognition and treatment of hypercholesterolemia. Hypercholesterolemia was diagnosed in 66 percent of patients, dietary recommendations were made in 46 percent, and lipid-lowering medication was prescribed in only 6 percent. Lipid profiles or high-density lipoprotein levels were determined in 22 percent, and thiazide diuretics were being prescribed for 32 percent. There was a trend toward greater recognition and treatment in patients with cholesterol levels greater than 7.75 mmol/L (300 mg/dL) and in patients less than 70 years of age. These results suggest that physician recognition of hypercholesterolemia is greater when compared with previous studies, but more aggressive diagnosis and intervention are needed. Greater utilization of lipid-profile analysis in hypercholesterolemic patients should also be encouraged.  相似文献   
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